The Ambient Temperature sensor is a negative temperature coefficient thermistor that is located at the center stay of the condenser. The Ambient Temperature Sensor signal is used by the A/C ECU when making calculations related to blower motor, temperature, and mode door calculations.
Air conditioner Control Module sets DTC B1238 if Ambient sensor has been detected over 4.9V for 0.3 seconds.
Item | Detecting Condition | Possible Cause |
DTC Strategy |
•
Voltage check |
•
Poor Connection in harness
•
Open in signal circuit
•
Shrot to battery in signal circuit
•
Faulty Ambient Temperature sensor
•
Faulty air condtioner control Module |
Enable Conditions |
•
IG KEY ON | |
Threshold value |
•
Ambient Temperature sensor has been detected over 4.9V for 0.3 seconds | |
Failsafe |
•
Displayed '--' and A/C control Module regards and controls it as 20℃(68℉) |
Temperature(℃/℉) | Resistance(㏀) | Temperature(℃/℉) | Resistance(㏀) |
-20/-4 | 284.5 | 50/122 | 10.8 |
0/32 | 97.5 | 70/158 | 5.2 |
25/77 | 30 |
